Verb Tense Consistency

There are three main verb forms for showing time or tense:

    Simple Tense

• does not use auxiliary verbs
   

• refers to specific time period during which
  
                 something happens
                                OR
                  something happened and is over
                                 OR
                   something will happen

             Simple present (action goes on now):  I sit

            Simple past:  (action happened and is over):   I sat

            Simple future  (action will happen):   I will sit

    Perfect Tense

• uses have, has, or had as auxiliary verb
   
• allows action to continue over time

             Present perfect (action happened and may still be going on):   I have sat

            Past perfect (action happened before something happened in the past):  I had sat

            Future perfect (action will be considered in the future, by which time it will have already happened):                                                                                                                                      I will have sat

    Progressive Tense  

• uses is, are, was, or were as auxiliary verb with -ing ending on main verb
   
• focuses on “progress” of action

             Present progressive (action is in progress right now):   I am sitting

            Past: progressive (action was in progress in the past):  I was sitting

            Future progressive (action will be in progress in the future):  I will be sitting

Each of the above tenses denotes a specific time for an action or event to take place.  Writers should be careful to use the exact tense needed to describe, narrate, or explain. 

In general . . .

• Do not switch from one tense to another unless the timing of an action demands that you do.
   

• Keep verb  tense consistent in sentences, paragraphs, and essays.

 Verb tense consistency on the sentence level

• Keep tenses consistent within sentences. 

• Do not change tenses when there is no time change for the action.
   

         INCORRECT: 

         CORRECT: 

Since there is no indication that the actions happened apart from one another., there is no reason to shift the tense of the second verb.

 Note another example. 

         INCORRECT:

         CORRECT:   

The above sentence means that Mary walks into a room at times.  The action is habitual present.  The second action happens when the first one does.  Therefore, the second verb should be present as well.

 Change tense only when there is a need to do so.
 Usually, the timing of actions within a sentence will dictate when the tense must change.

          CORRECT: 

 The first action will take place in the future; therefore, the second one will as well.

             CORRECT:

  The second action took place in the past; the first action occurred before the past action.  Therefore, the first action requires the past perfect tense (had + verb).

Verb tense consistency on the paragraph level

• Generally, establish a primary tense and keep tenses consistent from sentence to sentence. 

• Do not shift tenses between sentences unless there is a time change that must be shown.

          PRESENT TENSE PARAGRAPH

    All actions in the above paragraph happen in the present except for the future possibility dependent upon a
     present action taking place: " If a cat sees the bird, the cat will kill it."

          PAST TENSE PARAGRAPH

             

     All of the actions in the above paragraph happen in the past except for the possibility dependent upon
     one action taking place:  "If a cat saw the bird, the cat would kill it." 

Verb tense consistency on the essay level 

   1.  Use present tense when writing essays about

• your own ideas 
• factual topics
• the action in a specific movie, play, or book

          YOUR OWN IDEAS

        FACTUAL TOPIC

         ACTION IN A SPECIFIC MOVIE OR BOOK

NOTE:  When quoting from a work, maintain the present tense in your own writing, while keeping the original tense of the quoted material.

         EXAMPLE (quoted material is shown in  blue)

     2. Use past tense when writing about

• past events
• completed studies or findings,  arguments presented in scientific literature

         EXAMPLE - PAST EVENT

 Note the justified use of present tense in the last sentence (shown in blue).

         EXAMPLE - SCIENTIFIC STUDY

    3. Use future tense when writing about

• an event that will occur in the future.

    EXAMPLE - FUTURE EVENT

  Remember . . .

• Change tense ONLY when something in the content of your essay demands that you do so for clarity.

 Note how the following example incorporates  tense change as needed to clarify several time periods.